Container for dispensing liquid

ABSTRACT

A container for liquid comprises a substantially airtight body for storing liquid, a means for varying the pressure of gas above the level of liquid in the body of the container, e.g. resilient flexible container walls such as a squeeze bottle, an air pocket structure disposed at the lower end of the container, and in free liquid communication with the body of the container so as to allow entry of liquid from the body of the container into the air pocket structure. Air resides in the air pocket structure when the container is disposed with its lower end downwardly. An outlet passageway has an upper end which communicates near the top of the air pocket structure to be disposed in air in the air pocket and a lower end open to atmosphere exteriorly of the container and the air pocket. Such a container holds liquid therein without dripping. To discharge the liquid, the pressure on the body is increased, so as to cause liquid to rise through the air pocket structure, and issue liquid from the outlet passageway. Upon release of the applied pressure, air is sucked back in through the passageways so as to have a cleaning effect thereon. The structure allows storage of liquid ready for dispensing, but without risk of leakage or dripping, even when exposed to fluctuations in temperature of considerable magnitude.

FIELD OF THE INVENTION

This invention relates to containers for liquids, and more particularlyto outlet structures for dispensing quantities of liquid from suchcontainers.

BACKGROUND OF THE INVENTION

In many applications, there is a need for a liquid container which canbe simply and reliably operated to deliver a small quantity of liquidtherefrom, without resulting in deposit of residual liquid in theoutlet. In household applications, for instance, there is a need for aliquid dispenser which will deliver small quantities of liquid soap orcosmetic on demand, and remain in clean condition after use. Flexible,squeeze bottles with simple narrow nozzle apertures are commonly used,but such arrangements commonly result in fouled outlet apertures afteruse over an extended period of time. This is a particular problem withcontainers of thick, pastey liquids such as liquid soaps, hand creamsand other cosmetic preparations.

There is also a need for containers for semi-solid products such assoaps, shaving creams, cosmetic lotions and the like which can be keptin temperature variable environments such as personal bathrooms, showersetc. in an "outlet downward" condition for ease of operation, but whichwill not drip or leak from the outlet even when subjected to varyingenvironmental temperatures.

There have been proposals in the past for the provision of an air lockbetween a body of liquid in a container and the outlet conduit from saidcontainer, to guard against unwanted liquid leakage therefrom. Forexample, U.S. Pat. No. 1,127,387 Alger discloses a form of liquidsiphon, e.g. for use with automatic flush tanks and liquid meters, inwhich a temporary liquid seal is formed in the siphon pipe. The inletend of the siphon pipe is disposed within a liquid-containing tank, andis overlied by a bell-like structure which forms an air lock above theinlet pipe. The liquid seal in the outlet pipe of the siphon preventsadmission of air to the discharge leg of the siphon so as to ensure thatthe siphon catches in a solid stream. As the liquid rises in the tank,air is trapped and compressed in the bell. This has the effect offorcing the water down the U-tube outlet, to start the operation of thesiphon.

U.S. Pat. No. 3,797,513 Hazen shows an alternative arrangement of siphondischarge from a flushing tank, in which the inlet to the U-shapedsiphon tube within the tank is overlied by an inverted bell structure,forming an air lock at the tube inlet. Water is supplied to the tankfrom an outside source, to cause the water level in the tank to rise.This traps and compresses air in the bell, and prevents flow of waterdown the outlet tube until the water level in the tank reaches apre-determined level. Once this level is reached, water is forced fromthe U-trap, air is forced out of the bell and the siphon commencesoperation until the tank is substantially emptied. Then the cycle isrepeated, so as to give regular periodic flushing.

U.S. Pat. No. 2,989,215 Willingham discloses a dispenser for a containerfor liquids. The dispenser includes a spray nozzle, the inlet to which,inside the container, is surrounded by a measuring cup. The liquid mayonly enter the nozzle from the measuring cup. On inverting thecontainer, the measuring cup is filled with a pre-determined amount ofliquid. Then the container is operated, e.g. by squeezing, to dischargethe predetermined amount of liquid therefrom. No air lock arrangement isprovided in this disclosure.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a container and discharge means therefor,which can be operated to dispense quantities of liquid therefrom, viathe intermediary of an air pocket structure overlying the entrance tothe discharge passageway. There is provided a means for increasing thepressure in the space above the liquid level, for example a squeezablebottle. Liquid within the bottle is forced through the air pocket as aresult of the pressure increase, to discharge the liquid down the outletpassageway and out of the container. Immediately upon release of theapplied pressure, air is drawn back through the outlet passageway torestore the air pocket and to restore the normal pressure in the spaceabove the liquid. In so doing, the air flow serves to clean liquidresidues from the outlet passageway and to maintain it in satisfactory,sanitary condition. Moreover, in the arrangement according to theinvention, the amount of liquid discharged is proportional to theincrease in pressure created in the air-filled or gas-filled space abovethe liquid level in the container. Thus the amount of pressure appliedcan be regulated so as to discharge the required amount of liquidthrough the discharge arrangement. In addition, the air pocketarrangement guards against unwanted leakage from the container throughthe outlet, when the container is mounted in its normal, outletdownwards operative position, and even when subjected to varyingtemperatures.

BRIEF REFERENCE TO OF THE DRAWINGS

FIG. 1 is a diagrammatic representation of a container and dischargemeans therefor, illustrating the principle of operation of the presentinvention;

FIG. 2 is a cross sectional view of a practical embodiment of acontainer and discharge means according to the invention;

FIG. 3 is a similar cross sectional view of a second embodiment of theinvention.

In the drawings, like reference numerals indicate like parts.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to FIG. 1, there is diagrammatically illustrated thereina container 10 in the body of which is a liquid 12 extending up to alevel 14. An air space 16 is left, above the liquid level 14. Protrudingdownwardly through the bottom wall 18 thereof and sealed thereto is anoutlet passageway in the form of a conduit 20. An air pocket structurein the form of an inverted bell 22 is provided within the body ofcontainer 10, secured to the container at a location to overlie theinlet end 24 of the outlet conduit 20, but having free communicationwith the interior of the container 10 via slots 25. The container bodyis substantially sealed apart from the outlet conduit 20. When liquid iscontained in the container 10 and the container is then disposed asshown in FIG. 1, with the outlet conduit 20 extending downwardlytherefrom, a pocket of air is formed in bell 22, communicating with theoutlet conduit 20 and hence at outside atmospheric pressure. Liquidenters the bell structure 22 to a level 26, leaving air in the bell 22.In this manner, the container 10 and its contents can be stored in theposition shown. Liquid will not escape or drip from the outlet conduit20, whilst the container is thus left undisturbed. A cap is notnecessary.

In order to discharge material from the container, through the outletconduit 20, the pressure P in the space 16 above the liquid level mustbe increased by some suitable means. In the case where the container 10is a resiliently sided flexible bottle, this pressure increase can beachieved merely by squeezing. In other arrangements, the container wallsmay be mechanically compressed, the vessel may contain a plungerarrangement movable therein to increase pressure, or the gas above theliquid may be heated by suitable means. When this occurs, liquid level14 tends to fall, and liquid level 26 in the bell structure 22 tends torise, 22. As the pressure P increases, level 26 eventually rises abovethe top 24 of outlet conduit 20, and liquid starts to discharge throughconduit 20.

When pressure in space 16 is relieved, e.g. by releasing the squeeze onthe bottle, pressure P will be less than outside, atmospheric pressure,and consequently, air will be sucked in through conduit 20, through theair pocket structure 22, to bubble up through the liquid 12 to restorethe pressure in the space 16. The return of air through conduit 20,occurring substantially immediately after discharge of liquidtherethrough, has the effect of cleaning the liquid residues from theside walls of the conduit 20, to maintain it in a clean, sanitarycondition between operations. The use of a closure cap, except forshipping purposes, is thus rendered unnecessary.

The amount of liquid to be discharged through conduit 20 of a givenstructure as shown is proportional to the increase in pressure P inspace 16. The apparatus functions according to the general equation:

    H×sg+P=atmospheric pressure

where H represents the difference in level between liquid level 14 inthe main body of the container, and liquid level 26 in the air pocketstructure, P represents the pressure in the gas space above the liquidlevel 14, and sg represents the specific gravity of the liquid. It canthus be seen that any increases in pressure P above the liquid levelmust cause a corresponding decrease in H, the liquid head, to operate inaccordance with the above equation. Increase in pressure P thus causes acorresponding loss of liquid through the discharge outlet 20, to arrangefor the new, required value of H, the amount of discharged liquiddepending upon the amount of pressure applied above the liquid level.Upon release of the applied pressure, e.g. by relaxation of the squeezebottle, air is drawn in to restore pressure P, corresponding to thenewly established value of H resulting after the discharge of thequantity of liquid through the outlet conduit. In this way, the amountof liquid discharged is determined by the amount of pressure applied tothe space above the liquid.

The use of the air pocket structure 22 in accordance with the presentinvention ensures that the liquid is maintained within the containerwhilst the container is at rest, and that there is no risk of drippingor other leakage of the contents through the outlet conduit. The liquidlevel in the vicinity of the outlet conduit 20 is well below theentrance 24 to the outlet conduit, so that dripping and leakage areavoided. When the pressure is relaxed, air is drawn into the body of thecontainer through the outlet conduit, to clean and dry the outletconduit itself, to prevent residual drip therefrom as well as to preventaccumulation and resultant clogging of materials therein. It is ofcourse necessary that the container itself be substantially hermeticallysealed, apart from the aforementioned outlet conduit, for proper controlof the pressure above the liquid level.

With the structure according to the invention, there must be a certain,finite increase in pressure P above the liquid level, before any liquidissues from conduit 20, so as to cause a sufficient rise of liquid inthe air pocket structure 22. As a consequence, a device according to thepresent invention is eminently suitable for use in environments ofvariable temperatures. An example is the use for containing soaps,shampoos, cosmetics and the like in a personal bathroom or showercloset. A squeeze bottle equipped with outlet means as described hereincan be mounted on the wall of the shower closet, with the outletpassageway extending downwardly, and can contain shampoo, for example.When the shower closet is in use, the temperature therein may riseconsiderably, with consequent increase in pressure P within the bottle.This will cause rise of liquid level 26 in the air pocket structure 22,but no liquid will issue from outlet conduit 20 until there has been asufficient increase in P to raise liquid level 26 over the entrance 24of the outlet conduit 20. By suitable adjustment of the height of thebottom of the air pocket structure 22 relative to the top end 24 of theoutlet conduit, therefore, the device can be arranged to withstand therange of temperature changes without leakage, and without requiring theuse of a capped discharge conduit. In the embodiment shown in FIG. 1,the outlet conduit is height adjustable relative to bottom wall 18, bysliding adjustment, whilst structure 22 is fixed.

With reference to FIG. 2, the container 10 shown therein is a flexiblewalled, squeeze bottle, terminating at its lowermost end in a narrower,screw threaded neck 28. The neck 28 is releasably received in acomplementary upwardly presented female screw thread 30 on an outletclosure 32, through the intermediary of a resilient sealing gasket 34.The body of the closure 32, which is generally cylindrical in shape,contains therein an integral outlet passageway or conduit 20, the upperend 24 of which is disposed near the upper, screw thread 30 thereof, andthe lower end 36 of which projects beyond the bottom wall 18 of theclosure, to terminate in an enlarged radial bead 38. A snap-fittingreleasable cap 40 is fitted over the bead 38, to protect against leakageduring transportation.

The body of the closure 32 also contains therein an air pocket structure22 in the form of an inverted bell, having a radially outwardlyextending lip 41 which is a snap fit in a radial groove 42 in the bottomof the side wall of the closure 32. The side wall of bell 22 has aseries of radially presented slots 44 which allow liquid communicationbetween the body of closure 32 and hence the interior of container 10,and the bell 22. The bottom wall 18 of the closure 32 is provided withdownwardly extending integral legs 46 so that the assembly may befree-standing, clear of the lower end 36 of the closure outlet when cap40 is removed.

The operation of the device shown in FIG. 2 will be clear from the abovedescription and FIG. 1. When the assembly is put in the position shownin FIG. 2, liquid from container 10 enters the bell 22 through slots 44to form an air pocket between the body of liquid and the outlet conduit20. Cap 40 may be removed, and the liquid contents will not drip or leakfrom the outlet. The container will withstand temperature variations solong as liquid does not rise in the bell 22 sufficient to enter conduit20. To discharge material therefrom, container 10 is squeezed, to causeliquid to rise in bell 22 and discharge liquid down conduit 20. As soonas the squeezing pressure is relieved, the relaxation of the container10 acts to draw air in through conduit 20, thereby effecting cleaning ofthe conduit and restoring the air pocket in bell 22.

Container 10 is a disposable item, which when empty can be unscrewedfrom engagement with closure 32. Another, filled squeeze container 10can then be replaced in the closure. The closure may if desired be wallmounted, as a permanent receptacle for liquid containers. The closure issuitably made of semi-rigidplastics material. It is a simple, economical2-part construction with bell 22 being a simple snap fit in the closurebody as shown.

FIG. 3 shows an embodiment of the invention which is in many respectssimilar to that of FIG. 2. It also comprises a squeeze bottle 10containing liquid, the neck of which is threadably received in acomplementary threaded neck 48 of a closure 50. Within the closure 50 isa chamber 52 defining an air pocket and bounded at the topside by a topwall 54 on which the end of the container neck is disposed, the chamber52 being entirely exterior to the bottle 10. A depending conduit 56extends from the neck 48 to the closure 50 and through the top of andinto the lower part of the chamber 52, so that liquid from container 10can enter chamber 52, downwardly through conduit 56 when the containeris disposed neck downwards, as shown.

The top wall 54 and chamber 52 extend laterally forwardly a substantialdistance from conduit 56 forming a narrow forward chamber portion 58. Atthe lower forward extremity of chamber portion 58, there is provided anoutlet aperture 60, with a releasable cap 62 therefor the chamberportion 58 sloping downwardly from the outlet aperture 60 to the lowerportion of the chamber 52. The lowermost surface of closure 50 isprovided with legs 64 and a forwardly extending base 66, on which theassembly may rest. The base 66 and forward chamber portion 58 define abight formation therebetween, in which is located the outlet aperture60. Bottom recess 68 in the base provides a storage facility for cap 62.

It will thus be noted that the outlet aperture 60 in the embodiment islaterally displaced from the conduit 56, the chamber 52 and the airpocket structure. The operation is substantially the same as previouslydescribed. Liquid from container 10 will enter chamber 52 to a certainlevel therein. Increase of pressure above the level of liquid incontainer 10 will cause liquid to exit via outlet aperture 60. Releaseof pressure in container 10 will cause air to draw back through aperture60 and into chamber 52. This arrangement is particularly useful for afree-standing device, in which the user can place a hand between base 66and chamber portion 58, to receive material from aperture 60.

As noted in connection with the embodiment of FIG. 1, the height of thetop entrance 24 of outlet conduit 20 above the equilibrium level 26 ofthe fluid in the air pocket structure 22 determines the amount ofpressure to be applied before liquid is discharged. Similarly, thisheight provides the temperature change tolerance before discharge. It istherefore of advantage to make the outlet passageway adjustable relativeto the air pocket structure, to tolerate different temperaturevariations. In FIG. 1, this is done by sliding adjustment of the outletpassageway. In alternative embodiments, this can be achieved in otherways such as by rotation or angular adjustment of the outlet passagewayor the air pocket structure, resulting in alteration of the separationtherebetween.

Whilst specific preferred embodiments of the invention have beendescribed and illustrated in detail herein, these are not to beconstrued as limiting. The scope of the invention is limited only by thescope of the appended claims.

What I claim is:
 1. A liquid dispenser comprising:a squeeze bottle forcontaining a supply of liquid to be dispensed; an opening formed in theunderside of said squeeze bottle to enable the liquid to be insertedinto said squeeze bottle with said squeeze bottle in an invertedupwardly open position; and a closure for closing said opening; saidclosure forming a base for said squeeze bottle and including: means forsealingly connecting said closure to said squeeze bottle around saidbottle opening; a chamber defining an air pocket in an upper portionthereof; a liquid passageway connecting a lower portion of said chamberthrough said bottle opening to the interior of said bottle; and a liquidoutlet connecting said air pocket to the external atmosphere.
 2. Aliquid dispenser as claimed in claim 1, wherein said chamber is locatedentirely at the exterior of said bottle.
 3. A liquid dispenser asclaimed in claim 1, wherein said liquid passageway communicates with theinterior of said bottle through the top of said chamber.
 4. A liquiddispenser as claimed in claim 1, wherein said chamber includes adownwardly sloping chamber portion, said liquid outlet communicatingwith said downwardly sloping portion.
 5. A liquid dispenser as claimedin claim 1, wherein said closure comprises a cap for said bottle andsaid chamber is accommodated entirely within said cap.
 6. A liquiddispenser, comprising:a bottle for receiving and storing a supply ofliquid to be dispensed; said bottle defining in the lower end thereof anopening through which the supply of liquid can be fed into said bottle;means for closing said bottle opening; said closing means comprising aclosure member and means for connecting said closure member to saidbottle in a liquid tight manner around said opening; and said closuremember comprising an air pocket structure for retaining a pocket of air;a liquid passageway communicating from a lower portion of said airpocket structure through said bottle opening with the interior of saidbottle and a liquid outlet providing communication between said pocketof air and the exterior of said dispenser; and means for producing apressure increase within said bottle to expel liquid through said liquidoutlet.
 7. A liquid dispenser as claimed in claim 6, wherein said meansfor producing a pressure increase comprises a resiliently deflectablewall of said bottle.
 8. A liquid dispenser as claimed in claim 6,wherein said closure connecting means comprise readily separablyinterengaging portions of said closure member and said bottle.
 9. Aliquid dispenser as claimed in claim 8, wherein said bottle has at theunderside thereof a neck defining said opening and said interengagingportions comprise screw threads on said neck and said closure member.10. A liquid dispenser as claimed in claim 6, wherein said air lockstructure is provided at the exterior of said bottle.
 11. A liquiddispenser as claimed in claim 10, wherein said liquid passagewaycommunicates through the top of said air pocket structure and throughsaid opening with the interior of said bottle.
 12. A liquid dispenser asclaimed in claim 6, wherein said air pocket slopes downwardly from saidliquid outlet to said lower portion of said air pocket structure.